Last updated: August 27, 2025
September in Thun, Switzerland, is characterized by a tempered climate, with maximum temperatures reaching a comfortable 25°C (78°F) and averaging around 13°C (55°F). The month experiences a diverse range of conditions, where temperatures can dip as low as 1°C (34°F). With 105 mm (4.1 in) of rainfall spread over 13 days, this month showcases the transition into autumn, bringing an atmosphere of crisp freshness. Humidity levels hover at a notable 81%, contributing to the enchanting allure of the Swiss landscape, cloaked in mist and charm. Visitors can expect a delightful blend of warmth and coolness, ideal for exploring the scenic beauty of Thun.
As September arrives in Thun, Switzerland, a refreshing shift in temperatures marks the transition into autumn. With minimums of 1°C (34°F) and maximums reaching 25°C (78°F), the month presents a comfortable average of 13°C (55°F). This gentle cool-down from summer's warmth is accompanied by clear skies and vibrant foliage, inviting both locals and visitors to enjoy outdoor activities. The gradual decline in temperature sets the stage for the crispness of fall, making September an ideal time to explore Thun's picturesque landscapes, with its breathtaking lake and majestic mountains.
In September, Thun, Switzerland, experiences a moderate amount of precipitation, with 105 mm (4.1 in) spread over 13 days of the month. This amount is a slight decrease from the preceding months, as August saw sharper rainfall totals of 176 mm (6.9 in). Notably, September's weather serves as a transition from the lush, wet summer months into the cooler fall season. While the rainfall days remain consistent with the previous month, the overall precipitation reflects a gradual tapering off as the region prepares for the drier months ahead. This pattern of diminishing rainfall highlights a typical seasonal shift, inviting a crispness that hints at autumn's arrival.
In Thun, Switzerland, the humidity in September averages at a comfortable 81%, slightly higher than the summer months of July and August, which recorded 82% and 77% respectively. This seasonal shift indicates a gradual return to more humid conditions as autumn approaches. Notably, the humidity begins to rise again in October, reaching 89%, mirroring the winter months that generally hover around 91% in January and December. This trend showcases Thun's temperate climate, where humidity levels fluctuate throughout the year, creating a uniquely refreshing atmosphere as nature transitions from the warmth of summer into the crispness of fall.
As summer transitions into autumn, September in Thun, Switzerland, features a UV Index of 7, indicating a high exposure category and a burn time of 25 minutes. This drop from the peak summer months—where the UV Index reached a striking 10—suggests that while the days are getting shorter and cooler, caution is still necessary during outdoor activities. The changing UV levels reflect the gradual retreat of the intense summer sun, yet it's essential to remain vigilant in protecting your skin as you enjoy the crisp autumn air. For more information on UV levels throughout the year, check out Thun UV Index.
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September in Thun, Switzerland, welcomes a delightful transition as summer's warmth lingers with 322 hours of sunshine, reflecting a perfect balance between vibrant summer days and the promise of autumn. The month showcases a gradual decline in sunlight compared to the peak of July, which boasts an impressive 416 hours, yet it still outshines the earlier months of the year, such as January with just 169 hours. As the year progresses, the trend indicates a steady decrease in sunlight, from the sun-drenched days of summer through to the cloudier months of late autumn, with only 195 hours in December. September, with its crisp air and golden-hued landscapes, invites residents and visitors alike to enjoy the last remnants of the warm season, as nature begins its slow descent into the quieter months ahead.
In Thun, Switzerland, September marks the transition into autumn with a 40% chance of sunny weather. This figure is notable as it holds steady with August, suggesting that while summer is winding down, the potential for bright, clear days still lingers. Observing the seasonal trend, the likelihood of sunshine gradually increases from the depths of winter, culminating in a peak during the late spring and early summer months. As the year progresses, September emerges as a promising time to bask in the sun, paralleling earlier summer months like July and August, making it an enticing choice for outdoor activities before the colder months set in.
As summer begins to wane, September in Thun, Switzerland, experiences a gentle transition in daylight duration, offering 12 hours of sunlight. This marks a noticeable decline from the sun-drenched days of August, which boasted a generous 14 hours of daylight. Throughout the year, a clear pattern emerges: the longer days of spring and summer gradually retreat into the shorter, crisper days of autumn and winter. Following September, daylight diminishes further, dipping to 10 hours in October and 9 hours in November, echoing the shift towards the winter months. While the vibrant hues of early autumn linger, this gradual reduction reminds us of the cyclical dance of light and dark in the heart of the Swiss seasons.
As September breezes in Thun, Switzerland, the winds tend to slow down, averaging a gentle 1.4 m/s (3 mph)—just a slight drop from the summer months. This seasonal shift is part of a broader trend where wind speeds fluctuate throughout the year, with the winter months often experiencing slightly stronger gusts. Following the warmer, calmer days of summer, September's wind provides a subtle reminder of the impending autumn, as both locals and visitors can enjoy the serene atmosphere. The consistent calmness of September winds offers a perfect backdrop for picturesque lakeside strolls and cozy cafes, embracing the beauty of the changing season.
Weather in Thun varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Thun, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is generally mild, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 25°C (78°F), resulting in an average of 13°C (55°F). The month receives about 105 mm (4.1 in) of precipitation over 13 days, accompanied by a relative humidity of 81%. In contrast, January brings significantly colder conditions, with temperatures plummeting to a minimum of -19°C (-2°F) and peaking at 11°C (53°F), averaging -2°C (29°F). Though precipitation is slightly higher at 113 mm (4.5 in) over 11 days, the humidity increases to 91%, contributing to the stark contrast between the two months. For those interested in specifics, you can find more details at Thun weather in January.
When comparing the weather in September and February, distinct differences emerge. September boasts a milder range of temperatures, from a minimum of 1°C (34°F) to a comfortable maximum of 25°C (78°F), with an average temperature around 13°C (55°F). The month sees a good amount of rainfall, totaling 105 mm (4.1 in) over approximately 13 days, coupled with relatively high humidity at 81%.
In contrast, February is colder, with temperatures ranging from a chilly minimum of -16°C (3°F) to a maximum of 16°C (60°F) and an average of just 1°C (34°F). Although it experiences slightly less precipitation at 99 mm (3.9 in) over 11 days, the humidity rises to 89%. For a detailed look at February's weather patterns, you can visit Thun weather in February.
September and March present contrasting weather patterns, showcasing the transition between summer and spring. In September, the temperature averages around 13°C (55°F), with highs reaching up to 25°C (78°F) and lows of 1°C (34°F), making it notably warmer than March, which has an average temperature of 3°C (39°F) and can dip as low as -21°C (-6°F).
March experiences slightly more precipitation at 121 mm (4.7 in) across 15 days, compared to September's 105 mm (4.1 in) spread over 13 days, and the humidity is a bit higher in March at 87%, compared to September's 81%. This makes March feel quite different, not just in temperature but also in the overall atmosphere. For more detailed information, check out Thun weather in March.
When comparing the weather in September and April, notable differences arise in both temperature and precipitation patterns. September typically boasts milder temperatures, with averages around 13°C (55°F) and a maximum of 25°C (78°F), making it a more temperate month overall. In contrast, April experiences cooler conditions, with average temperatures around 7°C (45°F) and a minimum reaching as low as -11°C (12°F). Additionally, while September sees a higher total precipitation of 105 mm (4.1 in) spread over 13 days, April has slightly less rainfall at 88 mm (3.5 in) over just 11 days. Humidity levels are similar in both months, hovering around 81% in September and 84% in April, making it feel quite damp during both periods. For more detailed information, you can check Thun weather in April.
In comparing the weather between September and May, we see a distinct difference in temperature and precipitation patterns. September typically boasts a milder climate with minimum temperatures around 1°C (34°F) and maximums reaching up to 25°C (78°F), averaging 13°C (55°F). In contrast, May features cooler minimum temperatures of -5°C (23°F) and can peak at 28°C (82°F), with an average temperature of 11°C (51°F). Additionally, May experiences significantly higher precipitation, totaling 182 mm (7.2 in) over about 19 days, compared to September's 105 mm (4.1 in) over 13 days. Despite May's higher humidity at 80%, September is only slightly more humid at 81%. For more details on May weather, you can visit Thun weather in May.
In comparing the weather between September and June, June tends to be warmer overall, with average temperatures ranging from 3°C (37°F) to a maximum of 31°C (88°F), compared to September's milder 1°C (34°F) to 25°C (78°F). Precipitation is also more pronounced in June, receiving 197 mm (7.8 in) over 17 days, whereas September experiences 105 mm (4.1 in) on 13 days. Both months have high humidity levels, with June at 82% and September slightly lower at 81%. For more detailed information, you can check Thun weather in June.
In comparing the weather of September and July, it’s clear that July experiences warmer temperatures, with a minimum of 7°C (44°F) and an average of 17°C (63°F), peaking at 31°C (89°F). In contrast, September has cooler temperatures with a minimum of 1°C (34°F) and an average of 13°C (55°F), reaching a maximum of 25°C (78°F). July also sees more precipitation, totaling 197 mm (7.8 in) over 16 days, while September has 105 mm (4.1 in) over 13 days, indicating slightly drier conditions. Humidity levels are comparable, with July at 82% and September at 81%. For more detailed information, you can check Thun weather in July.
In comparing the weather between September and August, September tends to be cooler with a minimum temperature of 1°C (34°F) and an average of 13°C (55°F), while August sees warmer temperatures, with a minimum of 6°C (43°F) and an average of 17°C (62°F). Maximum temperatures in September reach 25°C (78°F), in contrast to August's higher peak of 30°C (86°F). Precipitation is also noticeably different, with September experiencing 105 mm (4.1 in) over 13 days compared to August's 176 mm (6.9 in) spread over 15 days. Humidity levels are slightly higher in September at 81%, compared to 77% in August. For more detailed information, you can check Thun weather in August.
September typically offers milder temperatures ranging from a minimum of 1°C (34°F) to a maximum of 25°C (78°F), with an average of 13°C (55°F). The month experiences about 105 mm (4.1 in) of precipitation over 13 days, coupled with a humidity level of 81%. In contrast, October sees a drop in temperatures, with a nighttime low of -2°C (29°F) and a daytime high of 21°C (71°F), averaging 8°C (48°F). Precipitation increases slightly to 122 mm (4.8 in), also occurring over 13 days, while humidity rises to 89%. Overall, October transitions into cooler and wetter conditions compared to the relatively warmer September. For more details, visit Thun weather in October.
September and November present notable contrasts in weather conditions. In September, temperatures range from a minimum of 1°C (34°F) to a maximum of 25°C (78°F), with an average of 13°C (55°F). The month sees 105 mm (4.1 in) of precipitation over 13 days, accompanied by a humidity level of 81%. In contrast, November experiences cooler temperatures, with a minimum of -9°C (17°F) and a maximum of 19°C (67°F), averaging just 3°C (38°F). Although it receives slightly less precipitation at 94 mm (3.7 in) over the same number of rainy days, humidity increases to 89%. For more specific details, you can check the Thun weather in November.
September and December present marked contrasts in weather, reflecting the transition from late summer to winter. In September, temperatures range from a mild 1°C (34°F) at night to a comfortable 25°C (78°F) during the day, with an average of 13°C (55°F). The month experiences 105 mm (4.1 inches) of rainfall spread over 13 days, coupled with a humidity level of 81%. In contrast, December sees much colder temperatures, with a minimum of -12°C (11°F) and a maximum of only 10°C (51°F), averaging around 0°C (32°F). Additionally, December is wetter, with precipitation totaling 169 mm (6.7 inches) over 17 days and a higher humidity level of 91%. For more specific details on December weather, you can check Thun weather in December.
As September rolls in, Thun experiences a unique transition from the warmth of summer to the crispness of autumn. With higher humidity levels and a noticeable increase in precipitation, this month stands out from the drier summer months. Temperatures can still reach a pleasant maximum of 25°C, but the average drops significantly, reflecting the shift in season. Frequent rain showers introduce a refreshing freshness to the atmosphere, setting the stage for the vibrant fall foliage to come. To discover more about how Thun's weather evolves throughout the year, visit Thun Climate.